Patents by Inventor Lars Villemoes

Lars Villemoes has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20180268831
    Abstract: An encoding system (400) encodes an N-channel audio signal (X), wherein N?3, as a single-channel downmix signal (Y) together with dry and wet upmix parameters ({tilde over (C)}, {tilde over (P)}). In a decoding system (200), a decorrelating section (101) outputs, based on the downmix signal, an (N?1)-channel decorrelated signal (Z); a dry upmix section (102) maps the downmix signal linearly in accordance with dry upmix coefficients (C) determined based on the dry upmix parameters; a wet upmix section (103) populates an intermediate matrix based on the wet upmix parameters and knowing that the intermediate matrix belongs to a predefined matrix class, obtains wet upmix coefficients (P) by multiplying the intermediate matrix by a predefined matrix, and maps the decorrelated signal linearly in accordance with the wet upmix coefficients; and a combining section (104) combines outputs from the upmix sections to obtain a reconstructed signal ({circumflex over (X)}) corresponding to the signal to be reconstructed.
    Type: Application
    Filed: May 21, 2018
    Publication date: September 20, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Lars VILLEMOES, Heidi-Maria LEHTONEN, Heiko PURNHAGEN, Toni HIRVONEN
  • Patent number: 10049683
    Abstract: This disclosure falls into the field of audio coding, in particular it is related to the field of spatial audio coding, where the audio information is represented by multiple signals, where the signals may comprise audio channels or/and audio objects. In particular the disclosure provides a method and apparatus for reconstructing audio objects in an audio decoding system. Furthermore, this disclosure provides a method and apparatus for encoding such audio objects.
    Type: Grant
    Filed: October 21, 2014
    Date of Patent: August 14, 2018
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Janusz Klejsa, Lars Villemoes, Toni Hirvonen
  • Patent number: 10043526
    Abstract: The present invention relates to transposing signals in time and/or frequency and in particular to coding of audio signals. More particular, the present invention relates to high frequency reconstruction (HFR) methods including a frequency domain harmonic transposer. A method and system for generating a transposed output signal from an input signal using a transposition factor T is described. The system comprises an analysis window of length La, extracting a frame of the input signal, and an analysis transformation unit of order M transforming the samples into M complex coefficients. M is a function of the transposition factor T. The system further comprises a nonlinear processing unit altering the phase of the complex coefficients by using the transposition factor T, a synthesis transformation unit of order M transforming the altered coefficients into M altered samples, and a synthesis window of length Ls, generating a frame of the output signal.
    Type: Grant
    Filed: October 13, 2015
    Date of Patent: August 7, 2018
    Assignee: Dolby International AB
    Inventors: Per Ekstrand, Lars Villemoes
  • Patent number: 10043528
    Abstract: The present document relates an audio encoding and decoding system (referred to as an audio codec system). In particular, the present document relates to a transform-based audio codec system which is particularly well suited for voice encoding/decoding. A transform-based speech encoder (100, 170) configured to encode a speech signal into a bitstream is described. The encoder (100, 170) comprises a framing unit (101) configured to receive a set (132, 332) of blocks; wherein the set (132, 332) of blocks comprises a plurality of sequential blocks (131) of transform coefficients; wherein the plurality of blocks (131) is indicative of samples of the speech signal; wherein a block (131) of transform coefficients comprises a plurality of transform coefficients for a corresponding plurality of frequency bins (301).
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: August 7, 2018
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Janusz Klejsa, Per Hedelin
  • Publication number: 20180211677
    Abstract: The present document relates an audio encoding and decoding system (referred to as an audio codec system). In particular, the present document relates to a transform-based audio codec system which is particularly well suited for voice encoding/decoding. A quantization unit configured to quantize a first coefficient of a block of coefficients is described. The block of coefficients comprises a plurality of coefficients for a plurality of corresponding frequency bins. The quantization unit is configured to provide a set of quantizers. The set of quantizers comprises a plurality of different quantizers associated with a plurality of different signal-to-noise ratios, referred to as SNR, respectively. The plurality of different quantizers includes a noise-filling quantizer; one or more dithered quantizers; and one or more un-dithered quantizers.
    Type: Application
    Filed: March 22, 2018
    Publication date: July 26, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Janusz KLEJSA, Lars VILLEMOES, Per HEDELIN
  • Patent number: 10032458
    Abstract: An apparatus for processing an input audio signal relies on a cascade of filterbanks, the cascade having a synthesis filterbank for synthesizing an audio intermediate signal from the input audio signal, the input audio signal being represented by a plurality of first subband signals generated by an analysis filterbank, wherein a number of filterbank channels of the synthesis filterbank is smaller than a number of channels of the analysis filterbank. The apparatus furthermore has a further analysis filterbank for generating a plurality of second subband signals from the audio intermediate signal, wherein the further analysis filterbank has a number of channels being different from the number of channels of the synthesis filterbank, so that a sampling rate of a subband signal of the plurality of second subband signals is different from a sampling rate of a first subband signal of the plurality of first subband signals.
    Type: Grant
    Filed: March 15, 2017
    Date of Patent: July 24, 2018
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Dolby International AB
    Inventors: Lars Villemoes, Per Ekstrand, Sascha Disch, Frederik Nagel, Stephan Wilde
  • Patent number: 10026408
    Abstract: Exemplary embodiments provide encoding and decoding methods, and associated encoders and decoders, for encoding and decoding of an audio scene which at least comprises one or more audio objects (106a). The encoder (108, 110) generates a bit stream (116) which comprises downmix signals (112) and side information which includes individual matrix elements (114) of a reconstruction matrix which enables reconstruction of the one or more audio objects (106a) in the decoder (120).
    Type: Grant
    Filed: May 23, 2014
    Date of Patent: July 17, 2018
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Lars Villemoes, Leif Jonas Samuelsson, Toni Hirvonen
  • Patent number: 10021502
    Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.
    Type: Grant
    Filed: November 22, 2017
    Date of Patent: July 10, 2018
    Assignee: Dolby International AB
    Inventor: Lars Villemoes
  • Patent number: 10015614
    Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.
    Type: Grant
    Filed: November 21, 2017
    Date of Patent: July 3, 2018
    Assignee: Dolby International AB
    Inventor: Lars Villemoes
  • Patent number: 10013991
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: July 3, 2018
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes
  • Patent number: 10015597
    Abstract: A multi-channel input signal having at least three original channels is represented by a parameter representation of the multi-channel signal. A first balance parameter, a first coherence parameter, or a first inter-channel time difference between a first channel pair and a second balance parameter, or a second coherence parameter, or a second inter-channel time difference parameter between a second channel pair are calculated. This set of parameters is the parameter representation of the original signals. The first channel pair has two channels, which are different from two channels of a second channel pair. Furthermore, each channel of the two channel pairs is one of the original channels, or a weighted combination of the original channels, and the first channel pair and the second channel pair include information on the three original channels.
    Type: Grant
    Filed: April 19, 2013
    Date of Patent: July 3, 2018
    Assignee: Dolby International AB
    Inventors: Heiko Purnhagen, Lars Villemoes, Jonas Engdegard, Jonas Roeden, Kristofer Kjoerling
  • Publication number: 20180182404
    Abstract: The invention provides an efficient implementation of cross-product enhanced high-frequency reconstruction (HFR), wherein a new component at frequency Q?+r?0 is generated on the basis of existing components at ? and ?+?0. The invention provides a block-based harmonic transposition, wherein a time block of complex subband samples is processed with a common phase modification. Superposition of several modified samples has the net effect of limiting undesirable intermodulation products, thereby enabling a coarser frequency resolution and/or lower degree of oversampling to be used. In one embodiment, the invention further includes a window function suitable for use with block-based cross-product enhanced HFR. A hardware embodiment of the invention may include an analysis filter bank, a subband processing unit configurable by control data and a synthesis filter bank.
    Type: Application
    Filed: February 26, 2018
    Publication date: June 28, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventor: Lars VILLEMOES
  • Patent number: 9990929
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: June 5, 2018
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes
  • Patent number: 9992601
    Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.
    Type: Grant
    Filed: November 21, 2017
    Date of Patent: June 5, 2018
    Assignee: Dolby International AB
    Inventor: Lars Villemoes
  • Patent number: 9978385
    Abstract: An encoding system (400) encodes an N-channel audio signal (X), wherein N?3, as a single-channel downmix signal (Y) together with dry and wet upmix parameters (C, P). In a decoding system (200), a decorrelating section (101) outputs, based on the downmix signal, an (N?1)-channel decorrelated signal (Z); a dry upmix section (102) maps the downmix signal linearly in accordance with dry upmix coefficients (C) determined based on the dry upmix parameters; a wet upmix section (103) populates an intermediate matrix based on the wet upmix parameters and knowing that the intermediate matrix belongs to a predefined matrix class, obtains wet upmix coefficients (P) by multiplying the intermediate matrix by a predefined matrix, and maps the decorrelated signal linearly in accordance with the wet upmix coefficients; and a combining section (104) combines outputs from the upmix sections to obtain a reconstructed signal (X) corresponding to the signal to be reconstructed.
    Type: Grant
    Filed: October 21, 2014
    Date of Patent: May 22, 2018
    Assignee: Dolby International AB
    Inventors: Lars Villemoes, Heidi-Maria Lehtonen, Heiko Purnhagen, Toni Hirvonen
  • Publication number: 20180137868
    Abstract: The invention provides methods and devices for stereo encoding and decoding using complex prediction in the frequency domain. In one embodiment, a decoding method, for obtaining an output stereo signal from an input stereo signal encoded by complex prediction coding and comprising first frequency-domain representations of two input channels, comprises the upmixing steps of: (i) computing a second frequency-domain representation of a first input channel; and (ii) computing an output channel on the basis of the first and second frequency-domain representations of the first input channel, the first frequency-domain representation of the second input channel and a complex prediction coefficient. The upmixing can be suspended responsive to control data.
    Type: Application
    Filed: December 20, 2017
    Publication date: May 17, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko Purnhagen, Pontus Carlsson, Lars Villemoes
  • Publication number: 20180139558
    Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.
    Type: Application
    Filed: December 20, 2017
    Publication date: May 17, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventor: Lars VILLEMOES
  • Publication number: 20180139559
    Abstract: A multi-channel decoder for generating a binaural signal from a downmix signal using upmix rule information on an energy-error introducing upmix rule for calculating a gain factor based on the upmix rule information and characteristics of head related transfer function based filters corresponding to upmix channels. The one or more gain factors are used by a filter processor for filtering the downmix signal so that an energy corrected binaural signal having a left binaural channel and a right binaural channel is obtained.
    Type: Application
    Filed: December 20, 2017
    Publication date: May 17, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventor: Lars VILLEMOES
  • Publication number: 20180137866
    Abstract: The invention provides methods and devices for stereo encoding and decoding using complex prediction in the frequency domain. In one embodiment, a decoding method, for obtaining an output stereo signal from an input stereo signal encoded by complex prediction coding and comprising first frequency-domain representations of two input channels, comprises the upmixing steps of: (i) computing a second frequency-domain representation of a first input channel; and (ii) computing an output channel on the basis of the first and second frequency-domain representations of the first input channel, the first frequency-domain representation of the second input channel and a complex prediction coefficient. The upmixing can be suspended responsive to control data.
    Type: Application
    Filed: December 20, 2017
    Publication date: May 17, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko Purnhagen, Pontus Carlsson, Lars Villemoes
  • Publication number: 20180137867
    Abstract: The invention provides methods and devices for stereo encoding and decoding using complex prediction in the frequency domain. In one embodiment, a decoding method, for obtaining an output stereo signal from an input stereo signal encoded by complex prediction coding and comprising first frequency-domain representations of two input channels, comprises the upmixing steps of: (i) computing a second frequency-domain representation of a first input channel; and (ii) computing an output channel on the basis of the first and second frequency-domain representations of the first input channel, the first frequency-domain representation of the second input channel and a complex prediction coefficient. The upmixing can be suspended responsive to control data.
    Type: Application
    Filed: December 20, 2017
    Publication date: May 17, 2018
    Applicant: DOLBY INTERNATIONAL AB
    Inventors: Heiko Purnhagen, Pontus Carlsson, Lars Villemoes